Known in the prior art is a manufacturing method in which such reinforcements are made directly on a part of a tire being manufactured from a continuous thread by projecting the said thread in the manner of a whip rather than in the form of plies that are incorporated when the tire is being assembled.
The term “thread” is to be understood in its broadest sense, covering a monofilament, a multifilament, a twisted cord or a folded yarn or equivalent assembly, this irrespective of the material of which the yarn is made or the treatment it may undergo, for example a surface treatment to encourage it to bond closely with rubber, or alternatively a rubberizing treatment encasing the said thread in a coat of rubber to allow it to adhere directly to the support when it is projected.
A device such as this is described in publication EP 248 301. FIG. 1 illustrates the main components which make up this type of apparatus.
The thread 1 is introduced into the device from a supply source (not depicted). The apparatus projects lengths of thread 10 onto a receiving surface S which may with equal preference be formed by the crown region of a tire being manufactured or by a separate support ring or, alternatively still, by a flat surface.
The device comprises:                feed means 11 for feeding thread 1 from a source of thread,        a rotary conduit 2 fixed to a shaft 20 constituting the axis of rotation R of the conduit, so that the outer radial end 21 of the conduit is directed substantially radially with respect to the axis of rotation, the conduit receiving the thread 1 via its central end 22, which is the opposite end to the outer radial end 21, from the feed means, the thread leaving via the outer radial end, the feed means controlling the linear rate of advance of the thread inside the rotary conduit,        means for rotating the rotary conduit, and        thread cutting means (31, 24) acting on the thread in such a way as to release a length 10 for each revolution of the rotary conduit.        
This device may further comprise a thread guide 4, to receive and guide lengths of thread, as described in publication EP 248 301, or alternatively in publication EP 845 348.
The method described in publication EP 248 301 has, as its subject, a method for producing a tire reinforcement, the reinforcement comprising adjacent and substantially parallel lengths of thread 10, in which each length of thread 10 is projected individually into its position on a receiving surface S. The lengths of thread 10 are projected by rotating means 5, the receiving surface and the thread having self-stick properties.
The rotating means 5 comprise                feed means 11 for feeding thread 1 from a source of thread,        a rotary conduit 2 of given length fixed to a shaft 20 of axis R constituting the axis of rotation of the said conduit, so that the outer radial end 21 of the said conduit is directed substantially radially with respect to the axis of rotation, the said conduit receiving the thread 1 via its central end 22 which is the opposite end to the said outer radial end 21 arriving from the said feed means, the said thread leaving via the said outer radial end, the said feed means controlling the linear rate of advance of the thread inside the said rotary conduit,        means for rotating the said rotary conduit, and        thread cutting means (24, 31).        
Hence, for further details regarding the device and the method of known type, it is suggested that the aforementioned publications be consulted.
Nonetheless it has become evident that, in practice, it is often difficult to operate this type of apparatus because of the large number of adjusting means and the high impact that variations in these have on the quality of the reinforcements produced.